The present invention is related to an improved linkage structure of a treadmill, and more particularly to a linkage structure of a treadmill in which two side by side arranged tread board frames are stably drivingly connected with each other to reversely alternately swing.
In a conventional treadmill, two tread boards are independently pivotally disposed on a seat body. Each tread board is equipped with a buffering restoring cylinder. After a user treads the tread boards, the buffering restoring cylinders buffer and restore the tread boards. According to such structure, the two tread boards are independently operated without being drivingly connected with each other. This leads to inconvenience in use of the treadmill.